a) Field of the Invention
This invention relates to an electric refrigerator for domestic or business use, and specifically to a thermoelectric refrigerator making use of a Peltier device.
b) Description of the Related Art
A conventional electric refrigerator employs a Flon-type refrigerant, and by making use of the latent heat of vaporization of the refrigerant, its refrigerating unit lowers the temperature to -20.degree. C. or lower to cool down the air inside the refrigerator. Accordingly, moisture contained in the air inside the refrigerating unit forms dew and this dew then freezes. Although the air has a relative humidity close to 100% in the vicinity of the refrigerating unit, its humidity becomes very low in an interior region where the temperature is higher than that in the refrigerating unit, for example, 3.degree. C. or so. A lower humidity is preferred for the storage of dried foods, cookies, candies, chocolates and the like in a refrigerator. However, for the storage of perishables, vegetables and the like, a low humidity accelerates a deterioration in freshness so that a low humidity is not a preferred storage atmosphere.
A variety of thermoelectric refrigerators making use of Peltier devices have been proposed recently. They are however accompanied by a drawback. For example, in a cold storage box making use of a Peltier device and having a capacity of from 10 to 15 liters, the interior temperature lowers to -5.degree. C. or lower when the outside temperature drops in winter or the like. As a consequence, the interior humidity becomes low so that the freshness of perishables, vegetables or the like is lowered.